<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		
		<link rel="stylesheet" href="bs/css/bootstrap.min.css" />
		<link rel="stylesheet" href="bs/css/bootstrap-theme.min.css"/>
		
		<style>
			
			.dropcontent{
				display: none;
				margin: 30px auto;
				background-color: #f9f9f9;
				min-width: 160px;
				box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
			}
			
			.dropcontent a{
				color: black;
				padding: 12px 16px;
				text-decoration:none;
				display: block;
			}
			.dropbtn{
				background-color: #4CAF50;
				padding: 16px;
				font-size: 16px;
				border: none;
				cursor: pointer;
			}
			
			.dropdown{
				position: relative;
				display: inline-block;
			}
			
			.dropcontent a:hover{
				background-color:#f1f1f1;
			}
			
			.dropdown:hover .dropcontent{
				display: block;
			}
			
			.dropdown:hover .dropbtn .dropcontent{
				background-color: #3e8e41;
			}
		</style>
	</head>
	<body>
		<div class="dropdown">
			<button class="dropbtn">下拉菜单</button>
			<div class="dropcontent">
				<a href="#">一项</a>
				<a href="#">二项</a>
				<a href="#">三项</a>
				<a href="#">四项</a>
			</div>
		</div>
		
	</body>
</html>
